My info came from a guy that works for Chrysler, but i also factored in a lot of other things, like the older dodge stratus and some others have mitsu engines in them, the eagle talon and eclipse are basically the same car(every generation, remember the Dodge Laser). I'm sure Mitsu wasn't going to do all the work, so chrysler had to come up with something on their end.
Plus, i'd hate to think Mitsu crapped a terd like the auto tranny and didn't flush out of the system. It just doesn't add up to the quality of work they are known for.